Rest assured, those of us working on implementation of this new residency have people just like you at the forefront of our minds. You will NOT be out of luck. Since you are a current 3rd year, most likely you will apply to and match in the traditional manner - to an internship + 4 year radiology residency, or a 5 year categorical program that includes the intern year. Two things may happen at the program you matched into - they will implement the new IR residency, or they won't. If they DO implement the IR residency, you will most likely be given the opportunity to switch into that program when you arrive. If they DON'T implement the new residency (either because they haven't gotten around to it yet or because they have no intention to do it, as some smaller programs may not have the appropriate infrastructure to support an IR residency), you will have two options when it comes time to apply for fellowship: either apply to a traditional IR fellowship (some will most likely still exist when it comes time for you to apply), or apply to one of the new "Independent IR Residency" Programs. These programs are a two year program that you start after completing your internship and four years of radiology residency. If you have completed enough IR rotations and procedures during your radiology residency (currently set at 14 months and 500 procedures, although not finalized), you will be able to enter one of these independent programs in the SECOND year of the two year program (so that you don't have to do 7 years).
The fine details of this implementation are still being worked out, but this is the general concept of what to expect. I hope this helps.